KVM: s390: provide counters for all interrupt injects/delivery

For testing the exitless interrupt support it turned out useful to
have separate counters for inject and delivery of I/O interrupt.
While at it do the same for all interrupt types. For timer
related interrupts (clock comparator and cpu timer) we even had
no delivery counters. Fix this as well. On this way some counters
are being renamed to have a similar name.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>